Africa2k
Wednesday, 12 January 2011 16:37
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Mohammed Umer (1959-2011): Former Africa2k leader and PAGES SSC member. *It is with great sadness that PAGES takes note of the demise of the charismatic Africa2k Group Leader Mohammed Umer, (PAGES SSC), Addis Ababa University, Ethiopia.
Africa2k is part of the PAGES 2k global network under Focus 2 “Regional Climate Dynamics” for the last two millennia. The network was established in Corvallis, Oregon, USA at the PAGES YSM/OSM meeting on 7 July 2009.
It is known that Africa is vulnerable to climate change, mainly through impacts on precipitation and through changes in the frequency and magnitudes of climate extremes. This vulnerability is linked to widespread poverty, mismanagement of natural resources, conflicts and dependence on rain-fed agriculture.
Assessments of climate variability in Africa are difficult due to:
1) in the near term, to the sparse spatial coverage and often short time span of available instrumental records, and
2) over the last two millennia as a result of the prevalence of semi- to hyper-aridenvironments in the extra-equatorial regions. These dry climates have generally precluded the long-term persistence of lakes and wetlands, which in temperate and tropical regions typically preserve long records of environmental change. The result is a regional dataset characterized by spatially disjunctive, temporally discontinuous records, often with unreliable chronological control and ambiguous palaeoenvironmental significance.
The Africa2k Working Group, considering the facts and the potential impacts of future climate change, found it necessary and timely to:
1) conduct an audit of existing palaeoenvironmental archives, compile and evaluate the significance of published material
2) collate these data to construct a pan-African synthesis of climate change spanning the last 2 kyr, and
3) use this synthesis to identify key areas for future work, including new archives that can provide reliable palaeoenvironmental information at annual to multi-decadal time scales. This will provide a basis for direct comparisons with general circulation model simulations (GCMs), and for assessing the range of natural climate variability within which humans and ecosystems have been operating effectively, and the extent to which climates may exceed this envelope under potential future scenarios.
